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TJ-II: Fast particles induced transport: ExB transport and asymmetries: Difference between revisions
TJ-II: Fast particles induced transport: ExB transport and asymmetries (view source)
Revision as of 10:44, 13 January 2021
, 13 January 2021→Description of the activity
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== Description of the activity == | == Description of the activity == | ||
The goal of this proposal is to investigate poloidal & toroidal asymmetries of ExB turbulent transport induced by AEs including experiments in the TJ-II plasma scenarios and simulations. | |||
Regarding simulations, a new Guiding Centre Tracking (GCT) code was recently developed to analyse the transport and losses of energetic ions in the presence of energetic-particle-driven instabilities. It was in particular applied to the case of energetic GAMs, showing the puzzling result that energetic ion transport can exhibit a chaotic behaviour <ref>D. Zarzoso et al 2018 Nucl. Fusion 58 106030 </ref> and also losses of energetic particles in the presence of EGAMs were characterized for the first time as anomalous losses, exhibiting a poloidal asymmetry reminiscent of the interaction between the energetic particle trajectories and the EGAM <ref>D. Zarzoso, D. del-Castillo-Negrete 2020 J. Plasma Phys 86 795860201</ref>. Such code was generalized to integrate the trajectories of guiding-centres in an arbitrary 3D geometry and in the presence of an arbitrary 3D electro-magnetic field. In this proposal, we intend to apply GCT to simulate trajectories of particles (thermal and energetic) in TJ-II in the presence of Alfvén eigenmodes. GCT simulations can provide the ExB transport and losses at any location of the device, which can be validated against experiments in order to determine the degree of asymmetry of the transport induced by Alfvén eigenmodes. | |||
Regarding experiments, the dual HIBP system <ref>A.V. Melnikov et al 2010 Nucl. Fusion 50 084023</ref> as well as edge Langmuir probes <ref>U. Losada et al., Plasma Physics and Contr. Fusion 2018</ref> <ref>F. Papausek et al., Master Thesis 2021</ref> have shown their capability to provide direct and simultaneous measurements of ExB transport induced by AEs at different poloidal, toroidal and radial locations in the TJ-II stellarator . | |||
With this in mind, the strategy of the TJ-II experimental program would be: | |||
1. Investigation of AEs localized in the edge region by means of edge probes and HIBP [reference shot 43706] and AEs identification. | 1. Investigation of AEs localized in the edge region by means of edge probes and HIBP [reference shot 43706] and AEs identification. | ||
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4. Measurements of fast ion losses at the edge of the TJ-II stellarator using a luminescent probe to monitor <ref>D. Jimenez Rey et al., 2008 Rev. Scientific Instruments 79 0935112008</ref> | 4. Measurements of fast ion losses at the edge of the TJ-II stellarator using a luminescent probe to monitor <ref>D. Jimenez Rey et al., 2008 Rev. Scientific Instruments 79 0935112008</ref> | ||
3. Comparative studies of plasma asymmetries of ExB transport due to AEs by using code simulations and TJ-II experimental results. | 3. Comparative studies of plasma asymmetries of ExB transport due to AEs by using GCT code simulations and TJ-II experimental results. | ||
== International or National funding project or entity == | == International or National funding project or entity == | ||